The present invention relates to a thermal insulation box, for example, for an automatic ice-making machine.
As shown in FIG. 15, a thermal insulation box employed in an automatic ice-making machine has a casing body 12. The casing body 12 is formed by disposing a pair of side panels 11 on the external sides of a right side wall and a left side wall of an ice bin 10 to be spaced away from each other crosswise. The ice bin 10 has an upward opening and a forward opening. An ice-making unit (not shown) suspended from a mounting frame (not shown) provided horizontally in an upper part of the casing body 12 is designed to be located in an upper space in the ice bin 10. Each side panel 11 has at the front a U-shaped portion 11a having a U-shaped cross section in plan view and at the upper edge an upper inward bent portion 11b (bent toward the ice bin), so that the U-shaped portion 11a and the upper bent portion 11b of the side panel 11 are adapted to be positioned by fitting the former to the front face and by placing the latter on the top face of the associated side wall of the ice bin 10, respectively.
A front frame 13 is attached to the front of the casing body 12 at a predetermined position lower than the top thereof. The front frame 13 prevents inward deformation and the like of the right and left sidewalls 12a (each sidewall being composed of the side wall of the ice bin 10 and the side panel 11) in the casing body 12 and secures a forward opening 12b for the casing body 12. The front frame 13 is box-shaped and opens backward (toward the ice bin) as shown in FIG. 15, and a heat-insulating material 14 formed separately is designed to be inserted into the frame 13. The front frame 13 is fitted to the casing body 12 by abutting both lateral side faces of the frame 13 against the inner faces of the U-shaped portions 11a and, in this state, fixing the former to the latter by caulking, respectively, followed by insertion of the heat-insulating material into the frame 13. Here, the front frame 13 is made of a suitable metallic material so that it can function as a magnetic attracting face for a magnet attached to a door (not shown), which opens and closes freely the forward opening 12b of the casing body 12.
A front panel 15 is removably attached to the front of the casing body 12. The front panel 15 covers the portion of the forward opening 12b upper than the location of the front fame 13. This front panel 15 is box-shaped and opens backward (toward the ice bin), as shown in FIG. 15, and a heat-insulating material 16 formed separately is designed to be inserted into the front panel 15. The front panel 15 has on the rear side a pair of engaging holes 15a near the crosswise ends thereof. The engaging holes 15a are engaged with screw collars 17 located on the front ends of the sidewalls 12a of the casing body 12 (front faces of the U-shaped portions 11a of the side panels 11), respectively, to achieve positioning of the front panel 15 with respect to the casing body 12. The front panel 15 has a positioning piece 15b extended downward from the rear lower edge thereof. With the positioning piece 15b being abutted against the front face of the front frame 13, the positioning piece 15b is designed to be fixed to the front frame 13 through a screw 18. Here, the front panel 15 has an engaging portion 15c formed along the rear upper edge thereof, which is engageable with a counterpart engaging portion 19b of a top plate 19 (to be described later).
A top plate 19, which closes an upward opening 12c of the casing body 12, is box-shaped and opens downward (toward the ice bin), and a heat-insulating material 20 formed separately is adapted to be inserted into the top plate 19. The opening of the top plate 19 is designed to be slightly larger than the outside dimensions of the casing body 12. With the top plate 19 being placed on the top of the casing body 12, the top plate 19 is fixed at both lateral side faces to the right and left side panels 11 with screws 21, respectively. The top plate 19 has an engaging slot 19a defined in the rear part thereof, which can be engaged with a latch 22 fitted to the rear face of the casing body 12, and also has a counterpart engaging portion 19b formed at the front, which can be engaged with the engaging portion 15c of the front panel 15. More specifically, the top plate 19 is designed to be placed on the top of the casing body 12 and to be screwed thereto at both lateral side faces with the latch 22 being engaged with the engaging slot 19a of the top plate 19 and with the counterpart engaging portion 19b being engaged with the engaging portion 15c of the front panel 15.
The thermal insulation box described above involves a problem that the front panel 15 is merely brought into face contact at the rear face with the front faces of the sidewalls 12a of the casing body 12, so that gaps are likely to be formed therebetween, and there is a fear that contaminated water, oil, dust, insects, etc. enter the ice bin 10 through these gaps.
While the front panel 15 is positioned by engagement of the engaging holes 16a with the screw collars 17 attached to the casing body 12, the engaging holes 15a are designed to have a large inside diameter so as to facilitate engagement with the screw collars 17, taking the trouble for carrying out accurate positioning of the front panel 15 for fixing it by screwing to the front frame 13. Meanwhile, it can also be pointed out referring to the top plate 19 that it takes the trouble for achieving positioning thereof with respect to the casing body 12, since the top plate 19 is designed to have outside dimensions large enough to achieve engagement of the front part and rear part thereof with the engaging portion 15c of the front panel 15 and with the latch 22, respectively.
The present invention was accomplished in view of the problems inherent in the prior art described above and to solve them suitably, and is directed to providing a thermal insulation box, which is easy to attach and can be kept always hygienically.
In order to solve the problems described above and to attain the intended object suitably, the thermal insulation box according to the present invention is provided with a front panel attached to a front part of a casing body having a forward opening so as to cover the forward opening; the front panel being packed with a foamed heat-insulating material; characterized in that the casing has front protrusions formed on the front face of the casing body; and fitting recesses which are formed on the rear face of the front panel and which are to be fitted to cover the front protrusions of the casing body.
In order to solve the problems described above and to attain the intended object suitably, the thermal insulation box according to another aspect of the present invention is provided with a top plate disposed on top of a casing body having an upward opening so as to cover the upward opening; the top plate being packed with a foamed heat-insulating material; characterized in that the casing has upper protrusions formed on the top face of the casing body; and fitting portions which are formed along the lower edge of the top plate and which are to be fitted to cover the upper protrusions of the casing body.